摘要:
Provided herein is a class of reversible thermal gel polymers, formulations thereof, methods for using, and methods for making said reversible thermal gel polymers. Reversible thermal gel polymers and formulations are provided having versatile chemical, physical, mechanical and/or optical properties beneficial for a range of applications including medical treatment. In some embodiments, the architecture and composition of the polymer allows for tunable selection of one or more physical properties supporting a particular application.
摘要:
A surgical simulator for electrosurgical training and simulation is provided. The surgical simulator includes one or more simulated tissue structures made substantially of a hydrogel comprising a dual interpenetrating network of ionically cross-linked alginate and covalently cross-linked acrylamide. Combinations of different simulated tissue structures define procedural-based models for the practice of various electrosurgical procedures including laparoscopic total mesorectal excision, transanal total mesorectal excision, cholecystectomy and transanal minimally invasive surgery. Methods of making the simulated tissue structures are also provided.
摘要:
Disclosed is a method to synthesize hydrogels with increased viscosity from a solution that contains water, a copolymer and a dissolved salt of an alkaline metal, an earth alkaline metal and/or an organic amine by addition of a zirconium compound as a crosslinker which comprises i) providing a copolymer containing 0.005 to 20 weight % of structural units of formula I, 4.995 to 40 weight% of structural units of formula II and 5 to 95 weight % of structural units of formula III wherein R 1 , R 4 and R 6 are independently of one another hydrogen or C 1 -C 6 -alkyl,R 2 , R 3 and R 5 are independently of one another hydrogen, a cation of an alkaline metal, of an earth alkaline metal, of ammonia and/or of an organic amine, R 7 and R 8 are independently of one another hydrogen or C 1 -C 6 -alkyhA is a covalent C-P bond or a two-valent organic bridge group, and B is a covalent C-S bond or a two-valent organic brigde group, and wherein the percentage of the structural units refers to the total mass of the copolymer, preparing an aqueous solution by adding the copolymer prepared in step i) to a solution comprising water and the salt of the alkaline metal, the earth alkaline metal and/or the organic amine, forming a network of a hydrogel by addition of at least one Zirconium- compound to the aqueous solution prepared in step ii), and selecting the amount of the salt of the alkaline metal, the earth alkaline metal and/or the organic amine in the hydrogel to range from 0.15 and 10 weight%, referring to the total mass of the hydrogel. The method can be used to prepare hydrogels used in fracturing operations.
摘要:
A self-assembling polymer (SAP) composition useful in subterranean formations such as oil wells is described. The composition includes a polymer, and linking molecules that result in association of polymer molecules in aqueous solution e.g., brines. An exemplary composition includes cyclodextrin, sodium dodecyl sulfate and partially hydrolyzed polyacrylamide.
摘要:
The present invention provides processes for making higher molecular weight, functionalized poly(meth)acrylamide polymer products. As an overview, the processes use (trans)amidation techniques in the melt phase to react one or more high molecular weight amide functional polymers or copolymers with at least one co-reactive species comprising at least one labile amine moiety and at least one additional functionality other than amine functionality. In practical effect, the processes of the present invention thus incorporate one or more additional functionalities onto an already formed or partially formed polymer rather than trying to incorporate all functionality via copolymerization techniques as the polymer is formed from constituent monomers. The methods provide an easy way to provide functionalized, high molecular weight poly(meth)acrylamide polymer products.
摘要:
The present invention relates to thermally expandable thermoplastic microspheres comprising a polymer shell made from ethylenically unsaturated monomers encapsulating a propellant, said ethylenically unsaturated monomers comprising from 21 to 80 wt% of methacrylamide and from 20 to 70 wt% methacrylonitrile, the total amount of methacrylamide and methacrylonitrile being from 70 to 100 wt% of the ethylenically unsaturated monomers. Furthermore, the invention relates to production and use of such microspheres.
摘要:
Die vorliegende Erfindung betrifft ein Verfahren zur Granulierung von teilchenhaltigem Material aus industriellen Prozessen, wobei dieses Material mit Feuchtigkeit absorbierenden organischen Polymermaterialien, bevorzugt Superabsorbern und/oder Hydrogelen vermischt wird, sowie die so erhaltenen Granulate und deren Verwendung.
摘要:
A membrane obtainable from curing a composition comprising (i) a curable compound comprising at least two acrylic groups and a quaternary ammonium group; (ii) solvent; and optionally (iii) a curable compound having one ethylenically unsaturated group.